Recently, organic EL display devices are gaining attention as a next generation flat panel display device such as those with full color display. The demand is rising for this organic EL display device, which is a self-luminescent display device having excellent viewing angles, good visual characteristics, low power consumption, and can be made thin.
This organic EL display device has a plurality of organic EL elements that are arranged in prescribed arrays, and the respective organic EL elements are provided with a first electrode (positive electrode) formed on the substrate with insulating characteristics, an organic layer having a light-emitting layer formed on the first electrode, and a second electrode (negative electrode) formed on the organic layer.
In general, the light-emitting properties of the organic EL element such as brightness and evenness are significantly lowered as compared to the initial state after the organic EL element is driven for a period of time. The causes of such deteriorations in light-emitting properties include the deterioration of the organic layer caused by the moisture in the outside air entering the inside of the organic EL element, and the peeling off or the like occurring between the organic layer and the electrode occurring due to the moisture.
Thus, an organic EL display device provided with a sealing member to protect the organic EL element from moisture is being proposed. More specifically, what is proposed is an organic EL display device provided with an organic EL element constituted of a first electrode, an organic light-emitting layer, and a second electrode stacked on a substrate, and a sealing member having water absorbing characteristics (sealing member formed of an ultraviolet curable resin such as an epoxy resin, for example) disposed on the periphery of the substrate at a gap from the organic light-emitting layer. The organic EL display device has a structure in which the height (vertical length) of the sealing member increases towards the outer edge of the substrate from the organic light-emitting layer side. It is disclosed that by having this type of sealing member, water entering from outside the device can be prevented and the deterioration of the organic layer can be suppressed (see Patent Document 1, for example).